Endoscopic stent delivery system and method

Abstract

A stent delivery system is disclosed that has an outer assembly and an inner assembly that accommodates a stent. The inner assembly further has an external assembly contact area projecting from its surface that frictionally contacts an inner surface of the outer assembly. The contact area is positioned at one end of the inner assembly, proximal to the stent accommodating area. Also disclosed is a method of using the stent delivery system.

1. A system for delivering a stent into an anatomical structure, the system comprising:
 an outer tubular structure having a proximal end, a distal end, an inner surface defining a lumen, and an outer surface, wherein the outer tubular structure has a translucent region at the distal end and the translucent region has a length less than a constrained length of a stent placed within the outer tubular structure, wherein the outer tubular structure is devoid of braiding along the length of the translucent region between the inner and outer surfaces; 
 an inner elongated structure having a proximal end and a distal end, the inner elongated structure being located within the outer tubular structure such that the distal end of the inner elongated structure substantially coincides with the distal end of the outer tubular structure; 
 a stent accommodating area on the distal end of the inner elongated structure, the stent accommodating area accommodating the stent; and 
 an external tubular structure contact area projecting from a surface of the inner elongated structure and located closer to a proximal end of the stent accommodating area than a distal end of the stent accommodating area, the external tubular structure contact area frictionally sliding against an interior surface of the outer tubular structure, 
 wherein the translucent region is coextensive with at least a portion of the stent accommodating area. 
 
   
   
     2. The system of  claim 1 , further comprising:
 a gap between an external surface of the inner elongated structure and the interior surface of the outer tubular member. 
 
   
   
     3. The system of  claim 1 , further comprising:
 at least one marker band on the inner elongated structure proximate the stent accommodating area. 
 
   
   
     4. The system of  claim 1 , wherein the external tubular structure contact area on the inner elongated structure is constructed of Pellethane. 
   
   
     5. The system of  claim 1 , wherein the external tubular structure contact area on the inner elongated structure comprises a plurality of external tubular structure contact areas projecting from the surface of the inner elongated structure. 
   
   
     6. The system of  claim 5 , wherein each external tubular structure contact area on the inner elongated structure is separated from other external tubular structure contact areas. 
   
   
     7. The system of  claim 6 , wherein each subsequently proximal external tubular structure contact area on the surface of the inner elongated structure increases in durometer from the distal end to the proximal end of the inner tubular structure. 
   
   
     8. The system of  claim 7 , wherein the most distal external tubular structure contact area on the surface of the inner elongated structure has a durometer measure of approximately 55D. 
   
   
     9. The system of  claim 8 , wherein there are three external tubular structure contact areas. 
   
   
     10. The system of  claim 9 , wherein the durometer measures of the three external tubular structure contact areas on the surface of the inner tubular structure from the distal end proximally are approximately 55D, approximately 65D, and approximately 75D. 
   
   
     11. A method of deploying a stent with respect to an anatomical structure, the method comprising:
 providing a stent delivery system, the system comprising:
 an outer tubular structure having a proximal end, a distal end, an inner surface defining a lumen, and an outer surface, wherein the outer tubular structure has a translucent region at the distal end and the translucent region has a length less than a constrained length of a stent within the outer tubular structure, wherein the outer tubular structure is devoid of braiding along the length of the translucent region between the inner and outer surfaces; 
 an inner elongated structure having a proximal end and a distal end, the inner elongated structure being located within the outer tubular structure such that the distal end of the inner elongated structure substantially coincides with the distal end of the outer tubular structure; 
 a stent accommodating area on the distal end of the inner elongated structure accommodating the stent; and 
 an external tubular structure contact area projecting from a surface of the inner elongated structure and located closer to a proximal end of the stent accommodating area than a distal end of the stent accommodating area, the external tubular structure contact area able to frictionally slide against an interior surface of the outer tubular structure, 
 wherein the translucent region is coextensive with at least a portion of the stent accommodating area; 
 
 inserting the stent delivery system through an insertion point in a body until the distal ends of the external tubular structure and the inner elongated structure are in a position within the anatomical structure; 
 moving the outer tubular structure proximally while maintaining the position of the inner elongated structure, thus exposing the stent accommodating area and releasing at least part of the stent into the anatomical structure; 
 continuing the proximal movement of the outer tubular structure with respect to the inner elongated structure until the stent is completely deployed into the anatomical structure; and 
 withdrawing the stent delivery system from the insertion point in the body. 
 
   
   
     12. The method of  claim 11 , wherein the stent delivery system further comprises:
 a gap between an external surface of the inner elongated structure and the interior surface of the outer tubular member. 
 
   
   
     13. The method of  claim 11 , wherein the stent delivery system further comprises:
 at least one marker band on the inner elongated structure proximate the stent accommodating area. 
 
   
   
     14. The method of  claim 11 , further comprising:
 before completely deploying the stent into the anatomical structure, moving the inner elongated structure proximally while maintaining the position of the outer tubular structure, thus retracting at least part of the stent from the anatomical structure back into the stent accommodating area; and 
 re-positioning the stent delivery system to a new position with respect to the anatomical structure. 
 
   
   
     15. The method of  claim 11 , wherein the external tubular structure contact area on the inner elongated structure is constructed of Pellethane. 
   
   
     16. The method of  claim 11 , wherein the external tubular structure contact area on the inner elongated structure comprises a plurality of external tubular structure contact areas projecting from the surface of the inner elongated structure. 
   
   
     17. The method of  claim 16 , wherein each external tubular structure contact area on the inner elongated structure is separated from other external tubular structure contact areas. 
   
   
     18. The method of  claim 17 , wherein each subsequently proximal external tubular structure contact area on the surface of the inner elongated structure increases in durometer from the distal end to the proximal end of the inner tubular structure. 
   
   
     19. The method of  claim 18 , wherein the most distal external tubular structure contact area on the surface of the inner elongated structure has a durometer measure of approximately 55D. 
   
   
     20. The method of  claim 19 , wherein there are three external tubular structure contact areas. 
   
   
     21. The method of  claim 20 , wherein the durometer measures of the three external tubular structure contact areas on the surface of the inner tubular structure from the distal end proximally are approximately 55D, approximately 65D, and approximately 75D.